Heating element



Sept. l0, 935. F. RAFFLES HEATING ELEMENT Filed Feb. 5, 1954 WWI Ill IIP PER Patented Sept. l0, 1935 l UNITED sTATEs 2,014,196 HEATING ELEMENT GFFICE Frank Raies, Chicago, Ill. Application lFebruary s, 1934, serial No. 709,639

2 Claims.

This invention relates to an improved heating element and has for one of its principal objects the provision of a self-contained electrical resistance unit whereby a far greater amount of heat can be concentrated at a given point than has heretofore been considered possible. v

One of the important objects of this invention is to provide an electrical heating, unit or the like which, although made available for small instruments and rather delicate operations, eliminates the necessity of a transformer or any resistance which has ordinarily been considered necessary with devices of this sort.

.smother important object of the invention is to provide a heating element wherein the desired temperatureis concentrated at the end of 'the element and over a relatively small area 'which is especially advantageous in devices o this sort. l

Another and still further important object is the provision in a heating element of a novel form of refractory support for the resistance wire which, although of small diameter, possesses considerable strength and which, in connection with a suitable refractory cement, will eiiectively guard against short circuiting.

lOne of the deilnite objects of this invention is to provide a heating element, which can be used in the form oi a pencil for pyrography and also for delicate soldering jobs and the lilre, wherein the source of heat is positioned on a porcelain or some other insulating support which, i

:in turn, is surrounded by a metal element to be Used in the transferring oi the heat to desired points, the element itself being supported in a pencil-style handle which'allows ior proper insulation against heat for the protection of the lisers 'fingers and hands.

Another and still further important object 'of the invention is the provision in a heating eleinent such as the type used infsoldering irons or the like o a special winding wherein a constant heat is always available at any xed voltage such as lic volts or 220 volts, and which can, iurthermore, be suitably and eiciently operated on both alternating and direct current.,

@ther and further important objects ci the invention will be apparent Jirorn the disclosures in the accompanying drawing and following speeldcation., p

The invention, in a preferred im. is illustrai-,ed in the drawing and hereinafter more fully described. i a

ln the drawing:

Figure 1 is an enlarged sectional view of ther improved heating element of this invention,

v showing the pencil-style holder. therefor. l

Figure 2 is a still further enlarged sectiona` View of the heating element itself and its insulating support. Y

As shown in the drawing:

y`The reference numeral l0 indicates generally a support composed of porcelain or some other suitable refractory material which has an opening i2 extending through the middle thereof, and through this opening is passed a wire l@ which is of the usual high resistance type whereby the passage of a current or electricity therethrough generates considerable heat.

The end of a porcelain tube orv support l0 is beveled as best shown at it in Figure 2, this bevel extending inwardly to the edge'oi the opening i2 and over this beveled edge passes the wire ill which is then brought down below the end of the element i@ and wound in helical shape around the surface thereof as best shown at it. The spaces between the windings o the wire it are filled with a suitable refractory and insulating cement 2li which prevents short circuits and also retains the wire windings it in desired position. A

The windings ill are very closely associated at the outer end of the support where the concentration of heat is desired, and toward the rear of the support, the windings are spaced much farther apart as shown at Z22 in Figure l, finally terminating in a pair ci extensions which are, in turn, connected to the ends ci the usual lamp cord 2d or the like.

This lamp cord is passed through a suitable opening formed in a handle which is preferably ot wood or some similar suitable inaterial and which may be of any desired shape to accomrnodate the hand and fingers of the user.

A band of cork or some other heat insulating material is usually positioned in a suitable groove formed in the end of the y handle element 2li, thereby providing ior additional heat insulating eects.

The heating element lt-Ut is itself positioned in a hollow metal holder 32 preferably cylindrical in 'shape and which, if desired, may be made pointed at` its end as shown at 34 for 'a still further and better concentration of the evolved dit heat. 'll'his metal heat transferring point is 50 the compact- 55 of the manufacture oi.' this installation on quite a small scale while, at the same time, the amount of heat units delivered is considerably greater" than those ordinarily possible with much larger and more bulky equipment.

'I'he closeness of the windings Il, together with the nature of the refractory insulating cement used and the qualities of the high resistance wire itself, permits of a considerable concentration of heat at the point Il of the metal heating element 32 which renders this device particularly desirable for pyrography, small soldering Jobs and the like.

Another feature is the bevel at Il on the end of the insulatingl support Il whereby the entire support may be more accurately and closely fitted into the tube I2 and whereby a greater quantity of heat is concentrated at the end of the tube which obviously is the point where the most heat is desired in operations of this kind and in using instruments of this type.

L am aware that many changes may be made yand numerous details of construction varied throughout a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than as necessitated by the prior art.

I claim as my invention: 1. A heating element, including an insulating tube, a high resistance wire passing through the tube and extending out of the end thereof and terminating inwindings around the exterior of said tube end, together withl a refractory cement surrounding the wire and maintaining the same s in position on the support, and insulating each coil from adjacent coils, and a metal tube in which said heating element is positioned, the end of said metal tube being exteriorly and interiorly beveled, and a corresponding bevel at the end i0 of the support for the resistance wire, a length of said resistance wire being positioned in said last-named bevel. 1 2. A heating element, including an insulating tube, a high resistance wire passing through the 15 tube and extending out of the end thereof and terminating in Vwindings around the exterior of said tube end, together with a refractory cement surrounding the wire and maintaining the same in position on the support, and insulating each coil 20 from adjacent coils, and a metal tube in which said heating element is positioned, the end of said metal tube being exteriorly and interioriy beve1ed,'and a corresponding bevel at the end of the support for the resistance wire, a length 25 of said 'resistance wire being positioned in said last-named bevel, and the whole mounted to iit closely in the correspondingly interior beveled end of the said metal tube.

FRANK RAFFLES. 30 

